Captain Jack has already found his likeness on a statue, a plushie and now Torchwood Wallpaper. There is lots of fan fiction online featuring the Captain, including this quick one set at Torchwood HQ. If music is your thing that's also an option, somebody at Outpost Gallifrey cooked up a theme song for the spinoff. (Also available here, if you aren't a member)
So far though, people have been making all the same sort of stuff that fans of any show do. So I am challenging Woodies to be more creative. I live right on the beach so my great craft idea has been to make Torchwood ashtrays out of burnt driftwood. I haven't found any buyers yet but it's still early days.